Generally, in an ink jet type printer which is a type of a liquid ejecting apparatus (hereinafter, referred to as a “printer”), printing is performed by ejecting ink (liquid) to a recording medium from a nozzle formed on a nozzle forming surface of a recording head (liquid ejecting head) mounted in a carriage. In this case, water of the ink in the nozzle is easy to evaporate from the opening of the nozzle, so that the clogging of the nozzle is easy to occur due to the increase of the viscosity of the ink in the nozzle. Accordingly, in such a printer, the clogging of the nozzle is to be eliminated by performing maintenance (cleaning, flushing, or the like) for forcibly discharging the ink in the nozzle on regular basis.
In addition, when the printer is pausing, water evaporation of the ink from the opening of the nozzle is to be restrained by sealing the nozzle forming surface of the recording head by a cap. However, humectant is added in the ink for improving ejection stability of the ink from the nozzle and the like, so that the humectant remains in the cap when the cleaning is performed. Accordingly, the humectant remaining in the cap not only absorbs the water in the cap but also deprives the water from the ink in the nozzle. As a result, there is a problem in that the viscosity of the ink in the nozzle is increased to cause ejection trouble of the ink.
Consequently, the printer has been proposed which restrains water to be deprived by a moisture retention component in the cap from the ink in the cap by reducing a ratio of the moisture retention component in the cap by ejecting the ink whose moisture retention component (humectant) is the smallest into the cap before the printer shifts to pausing state (for example see Patent document 1).
[Patent Document 1] JP-A-2001-26112